三角梅红色素的稳定性

Stability of Red Pigment in Bougainvillea Petals: Impact of pH, Temperature, and Chemical Agents

摘要:

该文研究了三角梅花瓣中红色素的稳定性，由于该色素在提取、保存和应用中无法避免加热、调节pH值以实现酶、微生物的灭活和水分的去除，在整个过程中三角梅色素的稳定性易受这些条件影响，为解决此问题，采用分光光度法对三角梅红色素的稳定性进行研究。结果表明：三角梅色素在pH值为7，温度为60 ℃，避光保存下最稳定；相较于还原剂（Na2SO3），氧化剂（H2O2）对三角梅色素稳定性影响大，加入稳定剂可以缓解氧化剂对三角梅色素稳定性的影响；苯甲酸钠、碳酸氢钠、柠檬酸、维生素C和山梨酸钾浓度为0.4 mol/L可以延缓三角梅色素的分解；金属离子Pb2+、Al3+、Na+对色素稳定性的影响不显著；Ag+、Bi2+会使色素吸光值变大，且颜色变成玫红色，Cu2+会使色素变成橙红色，在没有稳定剂的条件下Fe3+使色素变成血红色，因此在实验过程中应该避免与这几种金属离子接触。该研究结果为三角梅红色素的应用提供重要参考和指导。

Abstract:

The stability of the red pigment in Bougainvillea petals was examined during key processes such as extraction, preservation, and application, focusing on factors including heating, pH adjustment, and water removal for enzyme and microbial inactivation. The stability of the pigment was vulnerable to these conditions throughout the process. Using a spectrophotometric method, it was determined that the pigment exhibits maximum stability at a pH of 7, a temperature of 60 ℃, and when stored in the dark. The stability of the pigment was more significantly affected by the oxidant hydrogen peroxide than by the reducing agent sodium sulfite. The addition of stabilizers, such as sodium benzoate, sodium bicarbonate, citric acid, vitamin C, and potassium sorbate at a concentration of 0.4 mol/L, helped mitigate the impact of the oxidant on pigment stability. Metal ions such as lead(II), aluminum(III), and sodium(I) did not significantly affect the stability of the pigment. However, silver(I) and bismuth(II) increased the absorbance of the pigment, producing a rosy red color. Copper(II) caused the pigment to turn orange-red, and without stabilizers, iron(III) caused the pigment to turn blood-red. Avoiding contact with these metal ions is recommended during experiments. These findings provide valuable insights for the practical application of Bougainvillea red pigment.